Intrauterine systems and components thereof. The systems include an intrauterine device (IUD), an insertion device or applicator for inserting the IUD into the cervix of a female patient. The insertion device includes an elongated sheath an elongated inner member positioned within a lumen of the elongated sheath a handle with one or more elongated guides and a moveable sheath slider. Additionally, methods related to the insertion procedure, and methods of manufacture for the insertion device.